Fibrotic phenotype of IgG4-related disease.

A prompt response to glucocorticoids is a clinical hallmark of IgG4-related disease. However, manifestations characterised by prominent tissue fibrosis on histological examination can be less responsive to glucocorticoid therapy than other types of IgG4-related disease. These manifestations include retroperitoneal fibrosis, fibrosing mediastinitis, Riedel thyroiditis, orbital pseudotumor, and hypertrophic pachymeningitis, among others. To explain this discrepancy, a preliminary distinction into proliferative and fibrotic phenotypes of IgG4-related disease has been proposed on the basis of clinical presentation, pathological features, and response to immunosuppressive therapy. Implications of this classification for patient management remain an important area of investigation. In this Series paper, we aim to dissect the pathophysiology of tissue fibrosis in IgG4-related disease and discuss how clinicians should approach the management of fibrotic manifestations of IgG4-related disease based on the most recent diagnostic and therapeutic developments.

Typical Bone Scintigraphy Presentation of Erdheim-Chester Disease in a Patient Diagnosed With IgG4-Related Disease.

ABSTRACT: A 50-year-old woman presented a dry syndrome, joint pain, inflammatory syndrome, polyclonal hypergammaglobulinemia, and tubulointerstitial nephritis. Imaging studies (including FDG PET/CT) revealed infrarenal retroperitoneal fibrosis with periaortitis and hypermetabolic osteosclerotic lesions. Bone scintigraphy demonstrated intense uptake in the femoral, tibial, and radial regions, suggestive of non-Langerhans histiocytosis, specifically Erdheim-Chester disease. A bone biopsy confirmed the presence of IgG4-positive plasma cells but no histiocytes. The patient received corticosteroid therapy followed by rituximab, resulting in a complete response. This case suggests an atypical manifestation of bone lesions in IgG4-related disease, emphasizing the diagnostic challenge between IgG4-related disease and Erdheim-Chester disease.

Left Ureterocalycostomy With Ileal Interposition for Retroperitoneal Fibrosis in Patient With Erdheim-Chester Disease.

BACKGROUND: Erdheim-Chester disease (ECD) is a rare progressive non-Langerhans' cell histiocytic multisystem disorder with a broad spectrum of clinical manifestations, including infiltrative perinephric with ureteral involvement resulting in hydronephrosis, renal atrophy, and eventual renal failure. OBJECTIVE: To present a patient with ECD with bilateral renal/ureteral involvement managed with bilateral percutaneous nephrostomy tubes (PCNT) and trametinib who underwent bilateral robotic upper tract reconstruction, the first such published report. The video demonstrates only the left-sided repair, which posed specific challenges and demonstrates reconstructive techniques useful in complex upper tract repairs with limited tissue availability. MATERIALS AND METHODS: A 35-year-old male initially presented with baseline creatinine of 1.62 and split renal function; 30% right and 70% left by Lasix renogram. Extra-genitourinary manifestations of disease included cardiac hypertrophy and skin ulcers/lesions. Bilateral retrograde pyeloureterography showed proximal ureteral obliteration ∼4 cm bilaterally. Multiple management options were discussed including PCNTs, but patient elected for definitive repair. He was seen by Cardiology and Anesthesia and deemed to be optimized. He held his trametinib for 1week before surgery. We demonstrate a difficult ureteral dissection with fibrotic hilum preventing separation. Simultaneous ureteroscopy identified the distal extent of stricture which was excised, leaving a ∼15 cm gap. Downward nephropexy was performed with ultrasound guidance to identify an inferior calyx. Partial nephrectomy was then performed without vascular control due to hilar fibrosis. Ileal interposition was chosen to bridge the remaining ∼8 cm gap. Proximal ileo-calyceal and distal ileo-ureteral anastomoses were performed. We then placed a 30 cm × 7 Fr double-J ureteral stent in standard fashion. The ileum was secured to the renal pelvis to maintain a straight lie and an omental flap was secured in place. RESULTS: Immediate postoperative course was complicated by partial small bowel obstruction leading to a negative exploratory laparotomy and a subsequent episode of urosepsis. The patient is now voiding well without stents or PCNTs, without infections and with improving renal function, now with GFR (glomerular filtration rate) of 62 from 43 preoperatively. With aggressive hydration, patient has had no obstruction of the distal ureter with mucus. MRI Abdomen/Pelvis 6months later showed irregularity of the calyces with stable mild hydronephrosis. The patient continues to be medically managed on trametinib for his underlying disease, with surveillance for recurrent fibrosis and obstruction which has not yet occurred. CONCLUSION: Robotic ureterolysis and ureterocalycostomy with possible bowel interposition is a reasonable option for upper tract reconstruction in select patients with ECD.

IgG4-related retroperitoneal fibrosis induced by nivolumab and ipilimumab in a patient with non-small cell lung cancer: A case report.

IgG4-related diseases are adverse events that occur after receiving treatment with immune checkpoint inhibitors (ICI). This study reports the first case of IgG4-related retroperitoneal fibrosis after the administration of chemotherapy with nivolumab and ipilimumab (NI therapy). An 80-year-old man developed lower abdominal pain eight months after NI therapy was initiated. Although the primary lesion maintained its reduced size on computed tomography, there was an increase in the soft tissue shadows intensity around the abdominal aorta, bladder, and seminal vesicles, suggesting retroperitoneal fibrosis. Blood tests showed elevated IgG4 levels. Computed tomography-guided biopsy of the retroperitoneum showed B cell-dominant lymphocyte infiltration consistent with IgG4-related retroperitoneal fibrosis and characteristic CD8-positive lymphocyte infiltration, suggestive of the involvement of cytotoxic T cells. Based on the clinical, imaging, and pathological findings, the patient was diagnosed with IgG4-related retroperitoneal fibrosis due to ICI. Immunotherapy discontinuation alone did not result in improvement; therefore, steroid therapy was initiated. In clinical practice, IgG4-related retroperitoneal fibrosis can occur as an immune-related adverse event when administering anti-PD-1 and anti-CTLA-4 antibodies for cancer immunotherapy. Early steroid therapy could be effective in controlling this immune-related adverse event.

Clinical Characteristics of Retroperitoneal Fibrosis Patients at a Tertiary Hospital in Japan.

Retroperitoneal fibrosis (RPF) is a rare cause of hydronephrosis and progressive renal dysfunction with unidentified origin. RPF is categorized into idiopathic RPF with/without immunoglobulin G4 (IgG4)-related disease (IgG4-RD), and secondary RPF. Identifying the underlying cause is challenging and often associated with delayed diagnosis or therapeutic interventions. We investigated RPF's clinical characteristics based on different etiologies and factors that may help distinguish the underlying causes. We analyzed the cases of 49 patients with RPF that was radiographically diagnosed at our institution (2008-2022). The cohort was 77.6% males; 75.5% had idiopathic RPF and 24.5% had secondary RPF. Among the idiopathic patients, 54.1% had IgG4-RD. The patients were likely to have abdominal pain, lower back pain/lumbago, and constitutional symptoms including generalized fatigue and fever. The idiopathic patients were likely to have higher serum IgG4 and IgG levels and lower serum C3 levels compared to secondary RPF. The IgG4-RPF patients were likely to have higher serum IgG4 levels and lower serum C-reactive protein, ferritin, and C3 levels compared to the idiopathic RPF patients without IgG4-RD. These findings might reflect underlying systemic inflammatory responses. Comprehensive laboratory testing, including serum inflammatory markers and immunological panels, is recommended for radiologically diagnosed RPF patients.

3D Laparoscopic Ureterolysis for Retroperitoneal Fibrosis Secondary to Radical Hysterectomy and Radiation Treatment for Cervical Cancer: Results from the Oncological Institute, Cluj Napoca.

BACKGROUND: Ureterolysis represents the surgical treatment for retroperitoneal fibrosis. The aim of the study was to review the outcomes of patients who had undergone radical hysterectomy and radiotherapy for cervical cancer that later developed retroperitoneal fibrosis, for whom 3D laparoscopic ureterolysis was performed in our department and to review current published studies. METHODS: We present a series of cases consisting of 6 patients with secondary retroperitoneal fibrosis. In all cases, the intervention was performed by the same surgeon from the Oncological Institute "Prof. Dr. Ion Chiricuța" Cluj-Napoca, Romania. We carried out a literature review, searching in the PubMed and MEDLINE studies published between 2000 and 2021 relevant to the matter and a total of 12 papers were selected. We reviewed the functional outcomes of patients that underwent minimally invasive ureterolysis. RESULTS: 3D laparoscopic ureterolysis was performed in 6 patients. Mean operative time was 166 minutes and mean blood loss was 203 mL. No surgery required conversion. Five patients showed good functional results after ureteral stent removal. In one case, the patient developed acute pyelonephritis and the ureteral stents were kept. CONCLUSIONS: Laparoscopic ureterolysis for retroperitoneal fibrosis secondary to operated and radiation-treated cervical cancer represents one of the most complex and challenging surgeries in the urological field. From personal experience we conclude that in oncological centers with vast experience in laparoscopy this minimally invasive approach is feasible and safe. Published data, even though scarce, strengthens our results and the need for this surgery in patients with retroperitoneal fibrosis with urological impact. The laparoscopic approach comes with good functional results and with the advantages of faster post-operative recovery comparing to open surgery and comparable results with the precision and dexterity offered by the robotic approach, but with lower economic burden.

Perivascular Cuffing as the Sole Imaging Finding of Pancreatic Cancer.

BACKGROUND: Perivascular cuffing as the sole imaging manifestation of pancreatic ductal adenocarcinoma (PDAC) is an under-recognized entity. OBJECTIVES: To present this rare finding and differentiate it from retroperitoneal fibrosis and vasculitis. METHODS: Patients with abdominal vasculature cuffing were retrospectively collected (January 2011 to September 2017). We evaluated vessels involved, wall thickness, length of involvement and extra-vascular manifestations. RESULTS: Fourteen patients with perivascular cuffing were retrieved: three with celiac and superior mesenteric artery (SMA) perivascular cuffing as the only manifestation of surgically proven PDAC, seven with abdominal vasculitis, and four with retroperitoneal fibrosis. PDAC patients exhibited perivascular cuffing of either or both celiac and SMA (3/3). Vasculitis patients showed aortitis with or without iliac or SMA cuffing (3/7) or cuffing of either or both celiac and SMA (4/7). Retroperitoneal fibrosis involved the aorta (4/4), common iliac (4/4), and renal arteries (2/4). Hydronephrosis was present in 3/4 of retroperitoneal fibrosis patients. PDAC and vasculitis demonstrated reduced wall thickness in comparison to retroperitoneal fibrosis (PDAC: 1.0 ± 0.2 cm, vasculitis: 1.2 ± 0.5 cm, retroperitoneal fibrosis: 2.4 ± 0.4 cm; P = 0.002). There was no significant difference in length of vascular involvement (PDAC: 6.3 ± 2.1 cm, vasculitis: 7.1 ± 2.6 cm, retroperitoneal fibrosis: 8.7 ± 0.5 cm). CONCLUSIONS: Celiac and SMA perivascular cuffing can be the sole finding in PDAC and may be indistinguishable from vasculitis. This entity may differ from retroperitoneal fibrosis as it spares the aorta, iliac, and renal arteries and demonstrates thinner walls and no hydronephrosis.

A case of immunoglobulin G4-related retroperitoneal fibrosis and hypophysitis with antecedent respiratory disease followed by spontaneous remission and recurrence.

A 65-year-old man presented with apparent bronchopneumonia. After treatment with antibiotics, he showed eosinophilia. Computed tomography (CT) imaging revealed bilateral consolidation, ground-glass opacities with nodular consolidations, and pleural effusion. Lung biopsy showed organising pneumonia with lymphoplasmacytic infiltration in the alveolar septa and in the thickened pleura and interlobular septa. All pulmonary abnormalities spontaneously went into remission within 12 months. At 73 years old, a follow-up CT scan revealed small nodules in both lungs and the review of the head CT scan showed thickening of the pituitary stalk in studying prolonged headache. Two years later, he visited the hospital complaining of severe oedema on the lower extremities with high serum immunoglobulin (Ig)G4 186 mg/dl. A whole-body CT scan showed retroperitoneal mass surrounding aortic bifurcation and compressing inferior vena cava, pituitary stalk thickening and gland swelling, and enlarged pulmonary nodules. Anterior pituitary stimulation tests showed central hypothyroidism, central hypogonadism, and adult growth hormone deficiency with partial primary hypoadrenocorticism. Retroperitoneal mass biopsy showed storiform fibrosis and obliterative phlebitis with marked lymphoplasmacytic infiltration with moderate IgG4-positivity. Immunostaining of the former lung specimen revealed dense interstitial infiltration of IgG4-positive cells. These findings indicated metachronous development of IgG4-related disease in lung, hypophysis, and retroperitoneum, according to the recent comprehensive diagnostic criteria of IgG4-related disease. Glucocorticoid therapy ameliorated oedema, on the other hand, unmasked partial diabetes insipidus at the initial dose of the treatment. Hypothyroidism and retroperitoneal mass regressed at 6 months of the treatment. This case warns us that long-term follow-up from prodromal to remission is necessary for the treatment of IgG4-related disease.

IgG4-related disease and isolated retroperitoneal fibrosis: A narrative review.

Retroperitoneal fibrosis (RPF) can occur due to many etiologies and is categorized into idiopathic and secondary. Etiologies of secondary RPF include medications, autoimmune disease, malignancy, and IgG4-related disease (IgG4-RD). Although IgG4-RD usually involves multiple systems synchronically including the pancreas, aorta, and kidneys, it can present with isolated RPF without involvement of other organ systems. Caution must be exercised in these instances as the diagnosis should be confirmed based on specific clinical, radiographic, and histopathologic criteria. Such confirmation can affect the work-up and therapeutic approach as treatment with corticosteroids can lead to remission, both clinically and radiographically.

A Review on The Role of Environmental Exposures in IgG4-Related Diseases.

PURPOSE OF REVIEW: Immunoglobulin G4-related diseases (IgG4-RDs) are immune-mediated fibroinflammatory multisystemic conditions identified by the presence of tumefactive lesions with a rich infiltrate of IgG4-positive plasma cells, and often by a high IgG4 serum concentration. IgG-RDs have a prevalence of at least 1 case every 100,000 persons, and they are mostly diagnosed after age 50, with a male to female ratio of about 3:1. IgG4-RD pathophysiology is still uncertain: it has been proposed that both genetic predisposition and chronic environmental exposures may play a role by triggering abnormal immune activation that perpetuates the disease. The purpose of this review is to summarize the evidences supporting the hypothesis that certain environmental/occupational exposures can trigger IgG4-RDs, focusing on the possible role of asbestos in an emerging IgG4-RD called idiopathic retroperitoneal fibrosis (IRF). RECENT FINDINGS: Although some studies suggested a relationship between tobacco smoking and IgG4-RD risk, occupational exposures seem to have the most interesting effects. Positive history of blue-collar work increases the risk of developing an IgG4-RD, and mineral dusts and asbestos were the most strongly associated industrial compounds. Asbestos has been found to be a risk factor for IRF years before its classification as IgG4-RD, and later in two large case-control studies. In the most recent one, conducted on 90 patients and 270 controls, asbestos exposure conferred an increased IRF risk, quantified by odds ratios from 2.46 to 7.07. Further structured studies including serum IgG4 evaluation should be conducted to clarify the effect of asbestos on patients with confirmed diagnosis of IgG4-related IRF. Environmental exposures, especially of occupational origin, appear to play a role in the development of different types of IgG-RDs. In particular, although first suggested very recently, the relationship between asbestos and IRF deserves to be explored in more structured studies, especially because of the biological plausibility of the role of asbestos in IRF pathogenesis.

The Onset of IgG4-related Retroperitoneal Fibrosis under Administration of a TNF Inhibitor in a Rheumatoid Arthritis Patient.

An 80-year-old woman with rheumatoid arthritis during treatment with etanercept, a tumor necrosis factor (TNF) inhibitor, showed swelling of the salivary glands and retroperitoneal fibrosis, which was diagnosed as IgG4-related disease. Although some reports have shown the efficacy of TNF inhibitors for IgG4-related disease or retroperitoneal fibrosis, TNF inhibitors sometimes cause paradoxical reactions like psoriasis, and the mechanisms are considered to involve the upregulation of plasmacytoid dendritic cells and IFN-α, which is also common in patients with IgG4-related disease. This is a case report of IgG4-related retroperitoneal fibrosis with the possibility of a rare paradoxical reaction by a TNF inhibitor.

Role of transduodenal endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/FNB) for diagnosis of retroperitoneal fibrosis (Ormond's disease).

BACKGROUND: Retroperitoneal fibrosis (RPF), often referred to as Ormond's disease when it is of idiopathic origin, is a rare disease characterized by the presence of inflammatory infiltrates and periaortic masses in the retroperitoneum. For a definite diagnosis, a biopsy and subsequent pathological examination is required. Currently accepted methods for retroperitoneal biopsy include open, laparoscopic, or CT-guided approaches. However, transduodenal endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/FNB) for diagnosis of RPF has attracted only little attention in the literature. CASE REPORTS: We report two male patient cases who presented with leukocytosis, elevated C-reactive protein, and a suspicious retroperitoneal mass of unknown origin on computed tomography. One patient also reported left lower quadrant pain, whereas the other patient suffered from back pain and weight loss. In both patients, idiopathic RPF was successfully diagnosed by using transduodenal EUS-FNA/FNB with 22- and 20-gauge aspiration needles. Histopathology revealed dense lymphocytic infiltrates and fibrosis. The procedures lasted approximately 25 and 20 minutes, respectively, and in both patients no serious adverse events occurred. Treatment included steroid therapy and administration of Azathioprine. CONCLUSION: We demonstrate that using EUS-FNA/FNB to diagnose RPF is a feasible, fast, and safe method, which should always be considered as a first-line diagnostic modality. Hence, this case report emphasizes that gastrointestinal endoscopists are likely to play an important role in the setting of suspected RPF.

Importance of Awareness and Careful Follow-Up of Suspected IgG4-Related Periaortitis.

IgG4-related disease may cause large vessel vasculitis, which often affects males in their 60s. Here, we report a case of suspected IgG4-related periaortitis in a 76-year-old man with lower left-side chest pain and hypertension based on computed tomography findings of thickened lesions surrounding the abdominal aorta and mesenteric arteries after ruling out acute cardiovascular diseases. His serum IgG4 levels were high, but the C-reactive protein and D-dimer levels were within normal limits. Because IgG4-related periaortitis was suspected, the patient was carefully monitored for blood pressure control, inflammatory markers, and renal function. Steroid therapy was not initiated, however, due to the difficulties performing a biopsy targeting periaortitis to obtain a definitive diagnosis and possible severe complications. During follow-up observation, IgG4-related kidney disease was suspected based on a slight increase in the serum creatinine levels and a renal biopsy was considered. Just before performing the renal biopsy, we observed left renal hydronephrosis caused by spreading retroperitoneal fibrosis. Immediate ureteral stent implantation and initiation of steroid therapy successfully improved the renal function and decreased the serum IgG4 level, respectively. Although relatively rare, IgG4-related periaortitis/periarteritis and retroperitoneal fibrosis should be considered in the differential diagnosis of aortic diseases, even after ruling out serious major acute cardiovascular diseases. Cardiologists should also be aware of the possible progression and systemic spread of this disease.

New-onset retroperitoneal fibrosis following COVID-19 mRNA vaccination: Coincidental or vaccine-induced phenomenon?

The Pfizer-BioNTech mRNA vaccine is a US Food and Drug Administration-approved coronavirus disease 2019 (COVID-19) vaccine. Although it is reported to be safe and effective, immune dysregulation leading to autoimmunity has become an area of concern. Retroperitoneal fibrosis (RPF) is an immune-mediated fibroinflammatory disease characterized by the deposition of fibrous tissues, primarily around the abdominal aorta and iliac arteries. Herein, we report a case of RPF following Pfizer BioNTech COVID-19 mRNA vaccination. To the best of our knowledge, there have been no published reports on RPF after COVID-19 mRNA vaccination. A 58-year-old woman with no history of autoimmune diseases presented with acute onset of epigastric pain 5 weeks after the second dose of the Pfizer-BioNTech vaccine. She had been diagnosed with stage I breast cancer 9 years ago and was in complete remission on admission. Abdominal computed tomography showed preaortic soft-tissue infiltration around the origin of the superior mesenteric artery but no evidence of breast cancer recurrence. Considering the temporal relationship between current symptoms and vaccination and the absence of other possible causes, she was diagnosed with RPF secondary to Pfizer-BioNTech vaccine-induced autoimmunity. This case may raise awareness of the possibility of RPF development following COVID-19 mRNA vaccination.

Chronic periaortitis: A clinical approach.

Chronic periaortitis (CP) is a rare disease characterised by the presence of a fibro-inflammatory tissue typically enveloping the abdominal aorta, the iliac arteries and, in some cases, the nearby structures, such as the ureters and the inferior vena cava. Imaging plays a key role in the diagnosis and follow-up: computed tomography and magnetic resonance imaging scans are used to define the extension of the pathological tissue, whereas fluorodeoxyglucose positron emission tomography is the gold standard to establish the degree of its metabolic activity. CP must be distinguished from secondary forms of periaortic infiltration, which include malignant, infectious, and drug-related aetiologies. This review focuses on the clinical aspects of CP and the differential diagnosis with secondary cases, and aims to provide the clinician with a guide through this challenging clinical approach.

Combined therapy of prednisone and mTOR inhibitor sirolimus for treating retroperitoneal fibrosis.

OBJECTIVES: Retroperitoneal fibrosis (RPF) is a rare autoimmune disease with fibrous tissue growth and inflammation in retroperitoneum. Its current treatments involve long-term uptake of glucocorticoids (e.g., prednisone) for controlling inflammation; however, side effects are common. We strived for an improved therapy for fibrosis remission while reducing side effects. METHODS: We surveyed gene-disease-drug databases and discovered that mammalian target of rapamycin (mTOR) was a key signalling protein in RPF and the mTOR inhibitor compound sirolimus affected many RPF pathways. We designed a therapy combining a gradual reduction of prednisone with a long-term, stable dosage of sirolimus. We then implemented a single-arm clinical trial and assessed the effects in eight RPF patients at 0, 12 and 48 weeks of treatment by measuring fibrous tissue mass by CT, markers of inflammation and kidney functions by lab tests, immune cell profiles by flow cytometry and plasma inflammatory proteins by Olink proteomics. RESULTS: With the combined therapy, fibrous tissue shrunk about by half, markers of acute inflammation reduced by 70% and most patients with abnormal kidney functions had them restored to normal range. Molecularly, fibrosis-related T cell subsets, including TH2, TH17 and circulating TFH cells, were reduced and tumour necrosis factor and related cytokines restored to healthy levels. No severe long-term side effects were observed. CONCLUSIONS: Our combined therapy resulted in significant fibrosis remission and an overall regression of the immune system towards healthy states, while achieving good tolerance. We concluded that this new therapy had the potential to replace the steroid monotherapy for treating RPF.

Multidisciplinary diagnosis and management of inflammatory aortic aneurysms.

BACKGROUND: Inflammatory abdominal aortic aneurysms (IAAAs) are a variant involving a distinct immunoinflammatory process, with nearly one half believed to be associated with IgG4-related disease (IgG4-RD). METHODS: MEDLINE and Google Scholar searches were conducted for English-language publications relevant to inflammatory aortic aneurysms from January 1970 onward. The search terms included inflammatory aortic aneurysms, aortitis, periaortitis, IgG4-related disease, and retroperitoneal fibrosis. Relevant studies were selected for review based on their relevance. RESULTS: Morphologically, IAAAs are characterized by a thickened aneurysm wall often displaying contrast enhancement and elevated metabolic activity on fluorine-18 fluorodeoxyglucose-positron emission tomography imaging. A strong association exists with perianeurysmal and retroperitoneal fibrosis. Although the rupture risk appears lower with IAAAs than with noninflammatory abdominal aortic aneurysms (AAAs), the currently recommended diameter threshold for operative management is the same. Open repair has been associated with increased morbidity compared with noninflammatory AAAs, and a retroperitoneal approach or minimal dissection transperitoneal approach has been recommended to avoid duodenal and retroperitoneal structural injuries. Endovascular aneurysm repair has been increasingly used, especially for patients unfit for open surgery. It is important to exclude an infectious etiology before the initiation of immunosuppressive therapy or operative repair. Multimodality imaging follow-up is critical to monitor disease activity and secondary involvement of retroperitoneal structures by the associated fibrotic process. Maintenance of immunosuppressive therapy will be needed postoperatively for most patients with active systemic disease, especially those with IgG4-RD and those with persistent symptoms. Additional interventions aimed at ureteral decompression could also be required, and lifelong follow-up is mandatory. CONCLUSIONS: Preoperative multimodality imaging is a diagnostic cornerstone for assessment of the disease extent and activity. IgG4-RD is an increasingly recognized category of IAAAs, with implications for tailoring adjunctive medical therapy. Open surgical repair remains the procedure of choice, although endovascular aneurysm repair is increasingly being offered. Maintenance immunosuppressive therapy can be offered according to the disease activity as assessed by follow-up imaging studies.

Minimally invasive ureterolysis and intraperitonealization of ureter for idiopathic retroperitoneal fibrosis; single center analysis of an erratic disease.

INTRODUCTION: Idiopathic retroperitoneal fibrosis is a known cause of obstructive uropathy. Ureterolysis is done when medical management fails or the presentation is at an advanced stage. Conventionally ureterolysis without omental wrap has been considered incomplete. Our Institute has experience of laparoscopic or robotic ureterolysis with intraperitonealization of the ureter alone and no other adjunctive procedure. This study retrospectively assesses the result of the procedure with patients presenting with varying severity of disease. METHODS: From 2008, all patients who underwent laparoscopic or robotic ureterolysis were analyzed retrospectively for pre-operative management, operative findings, and post operative outcomes. RESULTS: We operated and released nine renal units in seven patients. Two of the nine cases were performed robotically completely and the rest was performed by laparoscopic approach. Median follow up was 60 months. All patients documented resolution of symptoms. The mean post-operative creatinine at 1 year was significantly decreased to 1.47 ± 0.49 mg/dl in comparison to preoperative creatinine (p < 0.05). The postoperative mean ESR decreased significantly from a preoperative value of 58.2 ± 19.41 mm to 15.8 ± 17.23. The nuclear scan revealed unobstructed drainage and radiological imaging revealed resolution of hydronephrosis and fibrosis in all. The mean GFR on the nuclear scan after 3 and 12 months of surgery was 36.3 ± 4.33 and 40 ± 3.77, respectively. Thus, there was significant increase noted in GFR at 3 and 12 months in comparison to preoperative GFR (p < 0.05). CONCLUSION: Laparoscopic/robotic ureterolysis with intraperitonealization alone is secure and durable procedure for idiopathic retroperitoneal fibrosis needing surgical release.

Idiopathic Retroperitoneal Fibrosis: What Is the Optimal Clinical Approach for Long-Term Preservation of Renal Function?

BACKGROUND: The aim of this study was to investigate the long-term effects of ureteral stenting and the exact timing of stent removal in favor of surgery in patients with idiopathic retroperitoneal fibrosis (IRF). SUMMARY: Medline research terms of "idiopathic retroperitoneal fibrosis" AND " medical therapy" OR "ureteral stenting" OR "surgical treatment" were done. Systematic reviews and observational and clinical studies were analyzed to obtain indication regarding the objective of the study for a narrative review. Ninety-two papers were analyzed. The treatment of IRF includes the monitoring of retroperitoneal fibrotic process spread and the prevention of abdominal organs entrapment. Treatment of ureteral obstruction includes medical therapy and ureteral stenting (US) or percutaneous nephrostomy (PNS) to overcome the worsening of renal function. Up to now, the timing of US or PNS removal is not yet clear, both for the complexity of evaluating the efficacy of the medical therapy and demonstrating the resolution of obstructive nephropathy. Moreover, it is not yet clear if the long-term ureteral stent placement or PNS is able to maintain an efficient renal function. Ureterolysis with a laparoscopic robot-assisted approach is now considered as an ultimate treatment for ureteral obstruction, limiting the progression of kidney impairment and improving the quality of life of patients, although nephrologists are generally abdicant regarding the potential switch toward the surgical approach. KEY MESSAGES: Prospective studies regarding the long-term effects of US on the renal function impairment in patients with IRF should be structured to obtain adequate information on the exact timing for the surgical approach.